1. Field of the Invention
The present invention relates to an object, a method, or a manufacturing method. In addition, the present invention relates to a process, a machine, manufacture, or a composition of matter. In particular, one embodiment of the present invention relates to a semiconductor device, a display device, a light-emitting device, a power storage device, a driving method thereof, and a manufacturing method thereof. In particular, one embodiment of the present invention relates to an organic compound, and a light-emitting element, a display module, a lighting module, a display device, a light-emitting device, an electronic appliance, and a lighting device in each of which the organic compound is used.
2. Description of the Related Art
In recent years, research and development of a light-emitting element (organic EL element) that uses an organic compound and utilizes electroluminescence (EL) have been actively promoted. In a basic structure of such a light-emitting element, an organic compound layer containing a light-emitting substance (an EL layer) is interposed between a pair of electrodes. By applying voltage to the element, light can be emitted from the light-emitting substance.
The light-emitting element is a self-luminous element and thus has advantages over liquid crystal displays, such as high visibility and no need for backlight when used as a pixel of a display, and is suitable as a flat panel display element. In addition, it is also a great advantage that a display including the light-emitting element can be fabricated as a thin and lightweight display and has very fast response speed.
In such a light-emitting element, light-emitting layers can be successively formed two-dimensionally, so that planar light emission can be obtained. Thus, a large-area light source can be easily formed. This feature is difficult to obtain with point light sources typified by incandescent lamps and LEDs or linear light sources typified by fluorescent lamps. Thus, the light-emitting element also has great potential as a planar light source which can be applied to a lighting device and the like.
Although displays or lighting devices including light-emitting elements can be suitably used for a variety of electronic appliances as described above, their performance and cost competitiveness have plenty of room to improve. In order to achieve this, materials that have good characteristics and are easily handled are required.
Patent Document 1 discloses a substance that has excellent characteristics as a host material of a phosphorescent element.